Buffett on the Value of Patient Optimism

.....

Stock prices will always be far more volatile than cash-equivalent holdings. Over the long term, however, currency-denominated instruments are riskier investments – far riskier investments – than widely-diversified stock portfolios that are bought over time and that are owned in a manner invoking only token fees and commissions. That lesson has not customarily been taught in business schools, where volatility is almost universally used as a proxy for risk. Though this pedagogic assumption makes for easy teaching, it is dead wrong: Volatility is far from synonymous with risk. Popular formulas that equate the two terms lead students, investors and CEOs astray.

It is true, of course, that owning equities for a day or a week or a year is far riskier (in both nominal and purchasing-power terms) than leaving funds in cash-equivalents. That is relevant to certain investors – say, investment banks – whose viability can be threatened by declines in asset prices and which might be forced to sell securities during depressed markets. Additionally, any party that might have meaningful near-term needs for funds should keep appropriate sums in Treasuries or insured bank deposits.

....

https://smeadcap.com/smead-strategies/smead-blog/entries/2015/03/03/buffett-on-the-value-of-patient-optimism/